A survey of fecal coliform bacteria in Canadarago Lake and its tributaries

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1 A survey of fecal coliform bacteria in Canadarago Lake and its tributaries Nick Mazziotta 1 INTRODUCTION Canadarago Lake (N , W ) is 390 m (1280ft) above sea level (Harr et al. 1980) and located within the towns of Richfield Springs, Otsego and Exeter in Otsego County, NY. This lake, along with Otsego Lake, makes up the lentic waters of the Susquehanna River watershed (Harr et al. 1980). Canadarago Lake is a dimictic water body formed by glacial activity and is considered eutrophic due to its tendency to lose oxygen in hypolimnetic waters. In addition to farmland, the lake is also surrounded by wooded hilltops and wetlands. The total surface area of the lake is 760 ha and it has a 175km 2 watershed (Harr et al. 1980). Tributaries to the lake include Oaks Creek, Hyder Creek, Herkimer Creek, Trout Brook and Ocquionis Creek. Richfield Springs wastewater treatment plant is located on Ocquionis Creek and discharges treated effluent 0.8 km upstream of the lake (Figure 1) (Bailey and Albright 2010). Prior to 1973, the discharge of secondarily treated sewage by the Richfield Springs wastewater treatment plant led to degraded water quality conditions in the lake (Harr et al. 1980). Since then, tertiary treatment by alum precipitation has been employed for phosphorous removal and has been very effective, though nitrogen is not removed. Phosphorus is most often the limiting factor in lake production. Excessive amounts of these nutrients are usually a primary cause of eutrophic character due to increases in algal blooms. Although this has been true in Canadarago Lake, recent monitoring implies that nitrogen may be limiting algal production and is related to the increased abundance of blue-green algal abundance as well as low nitrogen:phosphorus ratios (Bailey and Albright 2010). Many residential onsite wastewater treatment systems are also present around the lake; however, no inspection program is currently instituted to monitor their treatment performance. This was also the case in the Otsego Lake watershed until 2005, when an inspection and management program commenced; this program found that the majority of systems were not functioning properly due to antiquated and undersized designs, poor maintenance, and location relative to restrictive geologic and soil features (McIntyre 2010). It is likely that the condition and state of treatment systems along the shore of Canadarago is similar. These unmanaged systems have the potential to contribute nutrient loads to the lake. For these reasons, this study focuses primarily on fecal coliform bacteria levels along the lake shore, its major tributaries and outlet. A possible correlation between coliform and sediment content is also examined for the tributary and outlet sites. It is known that elevated amounts of pathogenic bacteria are usually associated with high amounts of turbidity present. Bacteria often attach to sediment particles and thus escape predation by invertebrates (Murdoch and Cheo 1996). Because soils contain proportionally more bacteria than water, runoff events have the potential to increase fecal coliform counts derived from soils (Murphy 2007). Fecal coliform bacteria are gram negative, non sporulating bacilli shaped bacteria that make up a group of indicator organisms used to evaluate water quality (APHA 1989). This group includes Pseudomonas, Streptococcus, Staphylococcus and Legionella species as well as 1 Canadarago Improvement Association Internship. Current Affiliation: SUNY Oneonta

2 Escherichia coli. The fecal coliform group is a subset of the total coliform group which includes species found in water, plants, and soil (Mack 1977; Mitchell 1992). Members of the fecal coliform group are naturally found in warm-blooded mammalian and bird intestines and thus, are not necessarily harmful to humans. High coliform colony counts, however, could indicate the likely presence of pathogenic organisms, including viruses (Coxsackie A,B, Hepatitis A, adenovirus types 3, 4) and parasites (Girardia, Cryptosporidium) present in the designated sampling area (APHA, 1989). High fecal coliform bacteria counts can also be related to the amount of phosphorus and nitrogen present in a water body. In addition, this group of bacteria can be easily cultured in the lab and thus make a good candidate for use as an indicator of other forms of pollution. They can be selectively grown in certain culture conditions where other types of bacteria would be restrained. Restriction factors to other bacteria include the use of lactose as a main energy source since fecal coliforms anaerobically ferment lactose in the intestine, the application of bile salts which they naturally withstand in the intestine to eliminate competition, and the ability to incubate the colonies at a temperature above the environmental norm (Cullimore 1993). METHODS Methods instituted throughout the summer 2010 survey were similar to those of 2009 (Bailey and Albright 2010). Water samples for fecal coliform analysis were collected weekly using 1 L Pyrex containers from 7 June 2010 to 19 July 2010 from each of the tributary and near-shore lake sites (Table 1, Figure 1). Samples were iced during transportation and processed the same day. Analysis was completed using the membrane filter (MF) technique (APHA, 1989) which involved running a series of sample volumes (5-100ml) through a low pressure vacuum in attempt to produce fecal coliform colonies per filter. Filters were then placed and seated inside sterile petri dishes on absorbent pads saturated in F C Base by Bacto growth media. All cultures were incubated in a water bath at 44.5 C for 24±2 hours. All glassware, including the sample bottles and graduated cylinders used for volume measurement, were sterilized using an autoclave set at 121 C for 5 mins. Colonies were counted after the incubation period and reported as colony forming units (CPUs) per 100mL. Samples for total suspended sediment analysis (TSS) were collected along with fecal coliform using the same 1 L Pyrex glass bottle per tributary site on 8 June, 7 July, and 19 July Total suspended sediment samples were analyzed using the gravimetric method (APHA 1989). Prior to sample processing, filters were dried in an oven at 105 C for 24±2 hours, placed in aluminum planchets and stored in a dessicator. After cooling, the filters were massed and recorded. A recorded volume of water sample ( ml) was passed through each filter, which was then dried in an oven at 105 C for 24±2 hours. The mass was recorded, allowing for the calculation of total suspended sediment. All sediment data are reported in mg/l.

3 Table 1. Descriptions and locations of sampling sites on Canadarago Lake and its tributaries. Site names altered from previous year as well as location for C.L. 4 due to GPS variation (Bailey and Albright, 2010). Tributary and Outlet Sampling Sites Oaks Creek Abbreviation: OK. C. East of the Village of Schuyler Lake on County Route 22; sampled north of bridge. Herkimer Creek Abbreviation: HK. C. North of the Village of Schuyler Lake on State Route 28; sampled east of bridge. Hyder Creek Abbreviation: HY. C. South of Dennison Road (NYSP boat launch access road) on State Route 28; sampled west of bridge. Trout Brook (Mink Creek) Abbreviation: T.B. Just north of Canadarago Lake on Elm Street Extension; sampled east of bridge. Ocquionis Creek North Abbreviation: O.C. 1 The beginning of Elm Street Extension, just south of Bronner Street; sampled south of bridge. Ocquionis Creek South Abbreviation: O.C. 2 End of Bloomfield Drive, through the rear gate of the waste treatment plant; sampled downstream of effluent discharge. Waste Treatment Plant Abbreviation: W.T.P. End of Bloomfield Drive, through gate and into plant, sampled from effluent pipe Lake Sampling Sites Lake Profiling Site Abbreviation: C.L. L.P Deepest spot encountered ( m; ft). (N W ) Canadarago 1: Abbreviation: C.L. 1 West side of Lake, northern most lake sampling spot. (N ' W ') Canadarago 2: Abbreviation: C.L. 2 West side of Lake, north of boat launch. (N W ) Canadarago 3: Abbreviation: C.L. 3 West side of Lake, south of boat launch. (N W ) Canadarago 4: Abbreviation: C.L. 4 West side of Lake, southern most lake sampling spot. (N W ) Canadarago 5: Abbreviation: C.L. 5 East side of Lake, south of Deowongo Island. (N ' W ') Canadarago 6: Abbreviation: C.L. 6 East side of Lake, east of Deowongo Island. (N ' W ')

4 O.C. 1 Ocquionis Creek Trout Brook O.C. 2 Waste Treatment Effluent T.B. C.L. 1 Hyder Creek C.L. 2 C.L. 4 HY. C. C.L. 3 C.L. L.P C.L. 6 Herkimer Creek HK. C. C.L. 5 OK. C. Oaks Creek Figure 1: Location of 2010 sampling sites on a bathymetric map of Canadarago Lake. Names of sites altered from previous year (Bailey and Albright, 2010). Lake RESULTS AND DISCUSSION Figure 2 summarizes the mean concentration of fecal coliform CPUs, including standard error bars, at each lake site over the seven sampling dates. It is important to note that the mean at C.L. 4 is particularly high due to a sample taken on 19 July which included an estimated 2,000 CPU/100 ml, or greater (precise counts were not possible since the lowest volume filtered produced much greater than 80 colonies). A logarithmic scale was used in order to make the other lake site results readable on Figure 2. No wildlife (i.e. waterfowl) was observed at the time of sampling that might have been responsible for the high concentration. This short term spike in fecal coliform CPU density could result from any number of potential occurrences. Though none were observed, wildlife (particularly waterfowl) could have been in the area prior to sample collection; improperly functioning or non-existent onsite wastewater treatment (septic) systems could also contribute bacteria. Previous to this date, the average colonies counted for this site was 36/100ml.

5 Overall, it was observed that there has been a general increase in colony counts in all lake sampling sites in comparison to previous data, with C.L. 1 and C.L. 4 being the most drastic (Bailey and Albright 2010; Bailey and Albright 2009). Note the 2008 data were only recorded from sites C.L. 2, C.L. 3 and C.L. 4 and the 2009 data were taken from these same sites and then switched to C.L. 1, C.L. 5, and C.L. 6 midway through the summer. This summer s survey examines all of these sites Colony Producing Units/100mL C.L. L.P C.L. 1 C.L. 2 C.L. 3 C.L. 4 C.L. 5 C.L. 6 Figure 2: Mean concentration of coliform producing units (CPUs) present at sites C.L. L.P., C.L. 1, C.L. 2, C.L. 3, C.L. 4, C.L. 5, and C.L. 6 on Canadarago Lake from 24 May to 19 July 2010 represented on a logarithmic scale. Tributaries Figure 3 summarizes mean CPU/100ml, including standard error bars, at each tributary site over seven sampling dates. Consistent sampling sites were maintained on the tributaries during the three years of sampling. For the third consecutive year, Trout Brook (T.B.) contained the highest concentration on average, while Oaks Creek (OK. C.) contained the lowest concentration of fecal coliforms (Bailey and Albright, 2010; Bailey and Albright, 2009). In addition, each site concentration, with the exception of Oaks Creek, increased relative to the past two years especially in Trout Brook, Hyder Creek (HY. C.) and Ocquionis Creek site 2 (O.C. 2) (Bailey and Albright, 2010; Bailey and Albright, 2009). Trout Brook again had the highest average CPU concentration (1574/100ml) while the two Ocquionis sites and Hyder Creek had average concentrations of approximately half that (777, 547 and 778 per 100ml, respectively).

6 Colonies/100mL OK. C HK. C. HY. C. T.B. O.C. 1 O.C. 2 Figure 3: Mean concentration of coliform forming units determined for the corresponding Canadarago watershed sites from 24 May to 19 July. Figure 4 illustrates mean TSS concentrations over three sampling dates in the summer of The results were similar to those documented in 2009 (Bailey and Albright 2010); despite the increase in TSS at the majority of sites since 2009, total suspended sediment has declined overall since 2008 (Bailey and Albright, 2009). A regression statistical analysis was performed in order to correlate the fecal coliform and sediment data sets. This analysis gave an R squared value of suggesting a slight correlation at best.

7 20 18 Suspended sediment (mg/l) OK.C. HK. C. HY. C. T.B. O.C. 1 O.C. 2 Figure 4: Mean total suspended sediment at Canadarago tributary sites by date, from 8 June to 19 July CONCLUSIONS Lake sites remain within contact recreation standards on average, though episodic spikes in CPU concentrations were observed during the 2010 monitoring period. On average, tributary sites were higher than the 200 CPU/100 ml threshold for safe contact recreation. Relatively high variability at some sites, as in the case of site CL 4, may indicate a situation in which episodic contamination events occur; such sites may be used to identify blatant sources of contamination without expending a great deal of effort or resources. Those sites with more consistent concentrations over the course of the study may contribute, but seem less prone to sporadic more substantial events that would contribute pathogens or large nutrient loads. Fecal coliform counts have increased in Canadarago Lake and its tributaries during the three years since the 2008 pilot study was conducted. Fecal coliform presence indicates potential influence from agricultural activities or improperly managed onsite wastewater treatment systems to the lake system; these sources should be considered in any future plans to manage watershed inputs to the lake.

8 REFERENCES APHA, AWWA, WPCF Standard methods for the examination of water and wastewater. 12 th ed. American Public Health Association. Washington, D.C. Albright, M.F., H.A. Waterfield and N. Mazziotta Continued monitoring of Canadarago lake and its tributaries, 2010 (interim report). In 43 rd Ann. Rept. (2010). SUNY Oneonta Biol. Fld. Sta., SUNY Oneonta. Bailey, C. and M.F. Albright Continued monitoring of Canadarago Lake and its tributaries. In 42 nd Ann. Rept. (2009). SUNY Oneonta Biol. Fld. Sta., SUNY Oneonta. Bailey, C. and M.F. Albright Pilot survey of Canadarago Lake and its tributaries, In 41st Ann. Rept. (2008). SUNY Oneonta Biol. Fld. Sta., SUNY Oneonta. Cullimore, Roy D. Practical Manual of Groundwater Microbiology. Boca Raton: Lewis Publishers, Print. Harr, T.E., G.W. Fuhs, D.M. Green, L.J. Helting, S.B. Smith and S.P. Allen Limnology of Canadarago Lake. In Bloomfield, J.A. (ed.) Lakes of New York State, Vol. III. Ecology of East-Central NY lakes. Academic Press, Inc., New York City, NY. Pp Kaufmann, R.K., & Cleveland C.J Environmental Science. McGraw-Hill. New York City, NY. Pp Mack, W.N. "Total Coliform Bacteria." Bacterial Indicators/Health Hazards Associated With Water. (1977): Print. McIntyre, w Otsego Lake management program for onsite wastewater treatment systems (OWTS). Prepared for Otsego lake Watershed Supervisory Committee, Cooperstown, NY. Mitchell, Ralph. Environmental Microbiology. New York: Wiley-Liss Inc., Print. Murdoch, T., Cheo, M., & O'Laughlin, K. (1996). Streamkeeper's Field Guide (second ed.). Everett, WA: Adopt-A-Stream Foundation. Murphy, Sheila General Information on Fecal Coliform. USGS Water Quality Monitoring/BASIN. Boulder, Colarado. Novotny, Vladimir, and Harvey Olem. Water Quality Prevention, Identification, and Management of Diffuse Pollution. 1. New York: Van Nostrand Reinhold, Print.

Monitoring the water quality and fecal coliform bacteria in the Upper Susquehanna River, summer 2004

Susquehanna River Water Quality Monitoring: Monitoring the water quality and fecal coliform bacteria in the Upper Susquehanna River, summer 2004 Joe Hill 1 ABSTRACT The monitoring of the Upper Susquehanna